Frequency Cutoff Checker
Drop a file and see its real high-frequency cutoff. Spot MP3-style ~16 kHz brick walls and AI/lossy top-octave loss that reveal a "WAV" came from a lossy source. Analyzed in your browser — nothing is uploaded.
How to tell if audio is MP3 or WAV
A file's extension lies easily — anyone can export a lossy MP3 and re-wrap it as a .wav, but that doesn't restore the audio the codec already deleted. The honest fingerprint is the high-frequency cutoff: lossy encoders like MP3 and AAC discard the top octave to save space, leaving a hard "brick wall" where the spectrum falls off a cliff. Typical MP3 lands a wall near 16 kHz; heavier compression and many AI generators (including Suno-style exports) cut even lower, below 15–16 kHz. A true WAV, FLAC or ALAC recording usually carries real, ragged energy all the way up past 18–20 kHz.
This tool decodes your file and measures the averaged magnitude spectrum, then finds the highest frequency still carrying meaningful energy. If that number sits under ~17.5 kHz with a clean shelf above it, your "WAV" almost certainly came from a lossy source — and no re-export will bring the missing highs back. They have to be rebuilt. That's exactly what TrackGleam's mastering does before it polishes: it reconstructs believable high-end so a dull, band-limited or AI-generated track sounds open again.
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FAQ
How can I tell if audio is MP3 or WAV?
Look at where the highs stop. Lossy codecs throw away the top octave, leaving a hard brick wall — often near 16 kHz for MP3, lower for heavier or AI compression. A genuine WAV/lossless file carries real energy past 18–20 kHz. This tool measures that cutoff so a re-wrapped lossy file can't hide.
Why does my AI or Suno track have a cutoff?
Many AI generators render through lossy pipelines or model limited bandwidth, so the export is missing its top octave — usually a sharp cutoff below 16 kHz. The loss is baked into the source, so re-exporting as WAV won't recover it; the high-end has to be rebuilt.
Does this upload my file?
No. Your audio is decoded and its spectrum measured entirely inside your browser with the Web Audio API. It never leaves your device.